REVIEW ARTICLE published: 25 February 2013 doi: 10.3389/fpls.2013.00023 Groundnut improvement: use of genetic and genomic tools Pasupuleti Janila1 *, S N Nigam1 , Manish K Pandey1 , P Nagesh1 and Rajeev K Varshney1,2 International Crops Research Institute for the Semi-Arid Tropics, Patancheru, Andhra Pradesh, India Generation Challenge Programme, c/o Centro Internacional de Mejoramiento de Maíz y Trigo, Mexico DF, Mexico Edited by: Scott Jackson, University of Georgia, USA Reviewed by: Mingsheng Chen, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, China Xiyin Wang, Hebei United University, China *Correspondence: Pasupuleti Janila, Groundnut Breeding, Building # 305, International Crops Research Institute for the Semi-Arid Tropics, Patancheru 502 324, Andhra Pradesh, India e-mail: p.janila@cgiar.org Groundnut (Arachis hypogaea L.), a self-pollinated legume is an important crop cultivated in 24 million world over for extraction of edible oil and food uses The kernels are rich in oil (48–50%) and protein (25–28%), and are source of several vitamins, minerals, antioxidants, biologically active polyphenols, flavonoids, and isoflavones Improved varieties of groundnut with high yield potential were developed and released for cultivation world over The improved varieties belong to different maturity durations and possess resistance to diseases, tolerance to drought, enhanced oil content, and improved quality traits for food uses Conventional breeding procedures along with the tools for phenotyping were largely used in groundnut improvement programs Mutations were used to induce variability and wide hybridization was attempted to tap variability from wild species Low genetic variability has been a bottleneck for groundnut improvement The vast potential of wild species, reservoir of new alleles remains under-utilized Development of linkage maps of groundnut during the last decade was followed by identification of markers and quantitative trait loci for the target traits Consequently, the last decade has witnessed the deployment of molecular breeding approaches to complement the ongoing groundnut improvement programs in USA, China, India, and Japan The other potential advantages of molecular breeding are the feasibility to target multiple traits for improvement and provide tools to tap new alleles from wild species The first groundnut variety developed through markerassisted back-crossing is a root-knot nematode-resistant variety, NemaTAM in USA The uptake of molecular breeding approaches in groundnut improvement programs by NARS partners in India and many African countries is slow or needs to be initiated in part due to inadequate infrastructure, high genotyping costs, and human capacities Availability of draft genome sequence for diploid (AA and BB) and tetraploid, AABB genome species of Arachis in coming years is expected to bring low-cost genotyping to the groundnut community that will facilitate use of modern genetics and breeding approaches such as genome-wide association studies for trait mapping and genomic selection for crop improvement Keywords: Arachis hypogaea, genetic variability, pedigree, disease resistance, phenotyping, QTLs, molecular breeding, genomic selection INTRODUCTION ECONOMIC IMPORTANCE AND USES Groundnut, also known as peanut, is an important oil, food, and feed legume crop grown in over 100 countries It covered 24 million area worldwide with a total production of 38 million tons in 2010 (FAOSTAT, 2010) In the last decade (2000–2010), the global groundnut production increased marginally The global annual increase in production was 0.4% which was due to both, an annual increase in yield by 0.1% and in area by 0.3% (Figure 1) The projected demand of groundnut in Asia alone by 2020 is expected to be 1.6 times more than the level of production in 2000 (Birthal et al., 2010) If the projected demands have to be met, the productivity and production of the crop has to increase at a much higher growth rate than the present one Asia and Africa account for 95% of global groundnut area where it is cultivated under rainfed conditions with low inputs by resource poor farmers Groundnut is a cash crop providing income and livelihoods to the farmer It also contributes to nutrition of farm families www.frontiersin.org through consumption of energy- and protein-rich groundnut kernels and provides nutritious fodder (haulms) to livestock Thus groundnut cultivation contributes to the sustainability to mixed crop-livestock production systems, the most predominant system of the semi-arid areas Groundnut is valued as a rich source of energy contributed by oil (48–50%) and protein (25–28%) in the kernels They provide 564 kcal of energy from 100 g of kernels (Jambunathan, 1991) In addition, the groundnut kernels contain many health enhancing nutrients such as minerals, antioxidants, and vitamins and are rich in mono-unsaturated fatty acids They contain antioxidants like p-coumaric acid and resveratrol, Vitamin E, and many important B-complex groups of thiamin, pantothenic acid, vitamin B-6, folates, and niacin Groundnut is a dietary source of biologically active polyphenols, flavonoids, and isoflavones As they are highly nutritious, groundnut and products based on groundnut can be promoted as nutritional foods to fight energy, protein, and micronutrient malnutrition among the poor Groundnut-based February 2013 | Volume | Article 23 | “fpls-04-00023” — 2013/2/21 — 17:49 — page — #1 Janila et al Groundnut: genetic and genomic tools FIGURE | Three-year moving center average for groundnut pod yield, production, and area harvested in world Plumpy’nut1 , a ready to use therapeutic food, has helped save the lives of thousands of malnourished children in Niger (UNICEF, 2007) Over 60% of global groundnut production is crushed for extraction of oil for edible and industrial uses, while 40% is consumed in food uses and others (such as seed for sowing the next season crop; Birthal et al., 2010) Groundnut oil is an excellent cooking medium because of its high smoking point (Singh and Diwakar, 1993) India, China, Myanmar, and Vietnam use groundnut oil for cooking purpose extensively The cake obtained after extraction of oil is used in animal feed industry, in preparing enriched easily digestible food for children and aged persons, and as soil amendment In Europe and North and South America about 75% of the production is used as food, while only 35% is used for the same purpose in Asia (Birthal et al., 2010) Peanut butter is the most popular groundnut product in the USA, Canada, and Australia Groundnut seed can be consumed raw (non-heated), boiled, and roasted and also used to make confections and its flour to make baked products The groundnut shells are used for making particle boards or used as fuel or filler in fertilizer and feed industry Groundnut haulms constitute nutritious fodder for livestock They contain protein (8–15%), lipids (1–3%), minerals (9–17%), and carbohydrate (38–45%) at levels higher than cereal fodder The digestibility of nutrients in groundnut haulm is around 53% and that of crude protein 88% when fed to cattle Haulms release energy up to 2337 cal kg−1 of dry matter Being a legume crop, groundnut helps in improving soil health and fertility by leaving behind N2 and organic matter in the soil TAXONOMY AND BIOLOGY The cultivated groundnut (Arachis hypogaea L.), an annual herb belonging to the family Fabaceae (Leguminosae), is classified into two subspecies, subsp fastigiata Waldron and subsp hypogaea Krap et Rig The subsp fastigiata contains four botanical varieties, var vulgaris, var fastigiata, var peruviana, and var aequatoriana The subsp hypogaea contains two varieties, var hypogaea and var hirsuta Each of these botanical types has http://www.nutriset.fr/fr/nos-produits/produit-par-produit/plumpy-nut.html Frontiers in Plant Science | Plant Genetics and Genomics different plant, pod, and seed characteristics (Krapovickas and Gregory, 1994) Groundnut is an allotetraploid (2n = 2x = 40) with “AA” and “BB” genomes All species, except the cultivated species (A hypogaea and A monticola) in Section Arachis, and certain species in Section Rhizomatosae, are diploid (2n = 2x = 20) The diploid progenitors, A duranensis and A ipaensis, contributed “AA” and “BB” genomes, respectively, to the cultivated groundnut (Kochert et al., 1996) The phylogenetic analyses based on intron sequences and microsatellite markers also provide evidence for this hypothesis (Moretzsohn et al., 2012) A single hybridization event between the diploid progenitors followed by chromosome doubling (Kochert et al., 1996) about 3500 years ago lead to origin of cultivated groundnut Southern Bolivia and Northern Argentina are thought to be center of origin of this crop (Gregory et al., 1980; Kochert et al., 1996) The center of diversity of the genus includes Western Brazil, Bolivia, Paraguay, and Northern Argentina (Gregory et al., 1980) A duranensis occurs throughout the region, while A ipaensis has only been found in Southern Bolivia The genetic diversity of the genus is classified into four gene pools (Singh and Simpson, 1994): primary gene pool consisting of A hypogaea and A monticola, secondary consisting of diploid species from Section Arachis that are cross-compatible with A hypogaea, tertiary consisting of species of the Section Procumbentes that are weakly cross-compatible with A hypogaea, and the fourth gene pool consisting of the remaining wild Arachis species classified into seven other sections Groundnut is a self-pollinated crop with cleistogamous flowers, but natural hybridization can occur to small extent where bee activity is high (Nigam et al., 1983) Flowering begins 17–35 days after seedling emergence depending on the cultivar and environmental conditions Flowers, simple or compound, are born in the axils of leaves and never at the same node as vegetative branch One or more flowers may be present at a node The stigma becomes receptive to pollen about 24-h before anthesis and remains so for about 12 h after anthesis, and the dehiscence of anthers takes place 2–3 h prior to opening of the flower in the morning Fertilization occurs about h after pollination Depending upon the prevailing temperatures, the peg or gynophore carrying the ovary and fertilized ovule on its tip appears in 6–10 days and grows to enter the soil (positively geotropic) where it develops into pods The tip orients itself horizontally away from tap root Groundnut grows well in well-distributed rainfall of at least 500 mm The growth and development is largely influenced by temperature in groundnut and the optimum air temperature is between 25 and 30◦ C The nutritional requirement of groundnut is different as the pods develop in the soil Calcium is an important nutrient required for pod and kernel development It is unique to groundnuts that the pods directly absorb most of the calcium, and therefore calcium fertilizers are applied in the pod zone at the peak flowering stage to ensure its availability to the pods TARGET TRAITS FOR GROUNDNUT IMPROVEMENT The aim of groundnut breeding programs across the world is to develop new varieties that meet the requirements of grower, processor, and consumer Thus the targeted traits for improvement in groundnut depend on the level of productivity achieved and consumers’ and industry requirements in a country In the USA, February 2013 | Volume | Article 23 | “fpls-04-00023” — 2013/2/21 — 17:49 — page — #2 Janila et al Groundnut: genetic and genomic tools where average productivity is high, the focus is more on improving food quality and flavor traits and freedom from mycotoxins in the produce In the developing countries, where yields are generally low, the focus is more on removing yield barriers besides improving yield per se YIELD PARAMETERS AND ADAPTATION Yield and yield contributing parameters are the most widely targeted traits of groundnut improvement programs worldwide Selection for yield per se has been the major basis for improving groundnut productivity in the world (Nigam et al., 1991), but gains from such selection have been low and slow due to large g × e interactions observed for these traits The pod yield is a function of crop growth rate, duration of reproductive growth, and the fraction of crop growth rate partitioned toward pod yield Therefore understanding physiology of yield is also essential to better target yield increase The important yield contributing parameters are: pod yield per plant, number of pods per plant, shelling outturn, and 100-seed weight Recently, physiological traits associated with yield (harvest index, transpiration-use-efficiency, etc.) are also receiving attention in breeding programs which have necessary infrastructure and resources Other traits not having direct bearing on yield such as ease in shelling, ease in harvesting (peg strength), number of seeds per pod (for specific uses), reticulation, beak and constriction of pod, kernel shape and color, and blanching ability are also important considerations to satisfy farmers’, processors’, and market demands For the development of dual purpose varieties, haulm yield becomes an important consideration in addition to pod yield In addition to quantity of haulm produced, its quality determined by nitrogen content and digestibility are also important to breed dual purpose varieties Crop duration and fresh seed dormancy in Spanish varieties are important adaptation traits The maturity duration should match with the length of growing period (LGP; 90 to over 150 days) available at a given location and conditioned by the soil moisture availability and climatic conditions (mainly temperatures and sunshine hours) Early maturity is an important trait in groundnut as it enables escape from stress conditions such as drought and frost and to fit in multiple cropping systems In situ germination, a consequence of lack of fresh seed dormancy leads to pod yield and quality loss in rainfed environments, particularly when rains coincide with the crop maturity stage STRESS TOLERANCE/RESISTANCE There is large gap between potential pod yield and the realized pod yield in most of the situations (Johansen and Nageswara Rao, 1996) Potential yield is defined as the maximum yield obtainable by the best genotypes in a specified agro-climatic environment when the known biotic and abiotic constraints are overcome The yield gap in the groundnut grown under water limiting conditions in rainfed areas is further aggravated by incidence of a host of diseases and insect pests Therefore, tolerance/resistance traits that offer protection against losses caused by biotic and abiotic stresses are important target traits In addition to protection to yield, resistance/tolerance to stress factors enhances the quality (nutritional, visual appearance, sensory attributes, free from toxins, and post-harvest keeping quality) of both, pods and haulms www.frontiersin.org that fetches better price in the market However, studies have shown that high yield potential and high degree of resistance not generally go together (Nigam et al., 1991), while the breeding programs target them together Therefore, in most of the breeding programs a balance is struck between the yield potential and level of resistance to avoid any possible yield penalty As a consequence, several varieties with high yield potential and moderate levels of resistance were bred and released for cultivation world over (see Some Accomplishments of Conventional Approaches) Drought and high temperature are the most important abiotic stresses that are widespread in groundnut-growing areas Depending on the time of occurrence, drought can be characterized as early season, mid-season, and end-of-season drought Mid- and end-of-season droughts are critical as they affect the pod yield and quality Further, end-of-season drought predisposes pre-harvest Aspergillus infection in the field that affects quality of produce Linked closely with drought is high temperature stress Two key stages for heat stress in groundnut are: flowering including microsporogenesis (3–6 days before flowering), and fruit-set (Craufurd et al., 2002, 2003) The CGIAR’s climate change for agriculture and food security (CCAFS) research has shown that high temperature stress (above 30◦ C) will be widespread in East and Southern Africa, India, South East Asia, and Northern Latin America, which are important groundnut-growing areas Thus, effort to breed varieties that can thrive and yield under both, drought and heat stress need to be intensified With the increase in problem soils (saline and acid) across the cultivated lands of the world, breeding for tolerance to salinity and aluminum toxicity in acid soils are considered important target traits for groundnut improvement in some countries such as China Groundnut is attacked by several diseases caused by fungi Late leaf spot (LLS) caused by Phaeoisariopsis personata (Berk & Curt.) Van Arx, early leaf spot (ELS) caused by Cercospora arachidicola Hori and rust caused by Puccinia arachidis Spegazzini are among the major foliar fungal diseases worldwide Aflatoxins are potent carcinogen produced by Aspergillus spp infection in seed forcing several countries to have strict regimes in place on permissible levels of aflatoxins in their imports A flavus is predominant species in Asia and Africa, while A parasiticus is in the USA Stem and pod rot, caused by Sclerotium rolfsii, is potential threat to groundnut production in many warm, humid areas, especially where irrigated groundnut cultivation is expanding Groundnut is also a host to several virus diseases, but only a few of them are economically important – groundnut rosette disease (GRD) in Africa, peanut bud necrosis disease (PBND) in India, tomato spotted wilt virus (TSWV) in the USA, peanut stripe potyvirus (PStV) in East and South East Asia, peanut stem necrosis disease (PSND) in pockets in Southern India, and peanut clump virus disease (PCVD) in West Africa (Nigam et al., 2012) Bacterial wilt, caused by Ralstonia solanacearum, is predominant among bacterial diseases of groundnut Globally, nematodes cause 11.8% yield loss in groundnut The root-knot nematodes, Meloidogyne spp and the lesion nematodes, Pratylenchus spp are important in groundnut (Sharma and McDonald, 1990) Aphids (Aphis craccivora Koch), several species of thrips (Frankliniella schultzei, Thrips palmi, and F fusca), leaf miner (Aproaerema modicella), red hairy caterpillar (Amsacta albistriga), jassids (Empoasca kerri and E fabae), and February 2013 | Volume | Article 23 | “fpls-04-00023” — 2013/2/21 — 17:49 — page — #3 Janila et al Groundnut: genetic and genomic tools Spodoptera are the major insect pests in groundnut, among which aphids, thrips, and Spodoptera have worldwide distribution and cause serious damage (Wightman and Amin, 1988) In addition to causing yield losses, aphids and thrips are vectors of important virus diseases Termites, white grubs, and storage pests also cause damage to groundnuts Groundnut borer or weevil (Caryedon serratus) and rust-red flour beetle (Tribolium castaneum) are the major storage insect pests in groundnut In most breeding programs across the world, breeding for resistance to diseases has received more attention than breeding for resistance to insect pest except when they are vector of viral disease Another important reason for this is the availability of the resistant sources for diseases in cultivated and wild Arachis species QUALITY PARAMETERS AND OTHER TRAITS Quality includes both, physical and chemical attributes Nutritional traits include oil, protein, sugar, iron and zinc content, fatty acid profile, and freedom from toxins, while the other quality parameters include visual and sensory attributes (consumer and trader preferred traits) and traits desirable in food/oil processing industries Breeding for quality parameters in addition to yield enhances the economic returns to the farmers and other stakeholders along the value chain Studies have shown that high oil content in groundnut is translated into economic benefits to both farmer and millers Similarly, the produce with desirable traits for confectionary uses fetches higher price in the market because of its export value Traits impacting on food and oil uses are also important; they include both quality and nutritional parameters Depending on the nature of use, low oil and high protein contents (for food use), high oil content (for oil use), and high oleic/linoleic fatty acid ratio (for longer shelf-life) are important targeted traits in advanced breeding programs The traits for confectionary uses in India are: greater proportion of sound mature kernels (SMK), flavor, 100 seed weight exceeding 55 g, >11% of sugar content, >24% of protein content, blanchability (>60%), and low oil content (55%) and stable performance have been targeted for improvement of oil quality (Janila et al., 2012) In addition, gene pyramiding has also been initiated targeting one major QTL each for rust and LLS resistance after identification of major QTL for LLS resistance on AhXII that explains up to 62% of phenotypic variation from the same donor (Sujay et al., 2012) Initiatives have been also taken at Chiba Prefectural Agriculture and Forestry Research Center in Japan, for marker-assisted introgression of mutant FAD2 alleles into an elite cultivar “Nakateyutaka” using a breeding line “YI-0311” as donor which had an O/L ratio of 48 (Koilkonda et al., 2012) Nakateyutaka, a Virginia type is a leading variety in Japan and has normal O/L ratio The ahFAD2A and ahFAD2b mutant alleles of the genotype YI-0311 were same as the previously reported mutational alleles found on high O/L groundnut genotypes (Jung et al., 2000) and used by Chu et al (2011) in their MABC program In addition to these ongoing molecular breeding activities the national programs for groundnut improvement in China and India have also initiated deployment of molecular breeding The next decade may probably witness a good number of groundnut varieties developed though integrated molecular breeding approaches TOOLS TO TAP ALLELES FROM WILD SPECIES Genetic variability holds the key for the success of breeding program and groundnut has a twofold problem in this respect: first is the low genetic variability due its nature of origin, and second, the reproductive isolation from its wild diploid species due to ploidy differences and sterility Wild Arachis species are known February 2013 | Volume | Article 23 | 10 “fpls-04-00023” — 2013/2/21 — 17:49 — page 10 — #10 Janila et al Groundnut: genetic and genomic tools as repositories of several desirable alleles, however, wider use of wild species in breeding has been hampered by ploidy and sexual incompatibility barriers, by linkage drag, and historically, by a lack of the tools needed to conventionally confirm hybrid identities and track introgressed chromosomal segments (Bertioli et al., 2011) They remain under-utilized due to burden of linkage drag although the crossing barriers are to some extent overcome through techniques of wide hybridization GWI and AB-QTL mapping are two important molecular marker-based approaches that enable enhanced utilization of alleles from wild species GWI of a small genomic region from wild species while keeping the genetic background of the cultivated genotype is a good means to explore the largely untapped reservoir of useful alleles of interest in wild species This is especially interesting in species like groundnut with narrow genetic base This approach has been widely utilized for introgression of favorable QTLs for various traits in other crops such as tomato, rice, wheat, and barley (Fridman et al., 2004; Wang et al., 2005; Liu et al., 2006; Schmalenbach et al., 2009) AB-QTL mapping facilitates simultaneous discover of QTLs and development of elite genotypes (Tanksley and Nelson, 1996) AB-QTL mapping was used in tomato to breed an elite processing line (Tanksley et al., 1996) In groundnut, Foncéka et al (2009) used AB-QTL approach to develop a genetic linkage map of wild genome introgression into cultivated background through utilization of synthetic amphidiploid between A duranensis and A ipaensis, and also derived CSSLs and AB populations The CSSLs and AB populations facilitate characterization of different segments of genome of wild species contributing for resistance to foliar diseases and/or any other desirable trait Once these different segments and their roles are determined, it is then possible to track them along the back-crosses using molecular markers for use in breeding programs AB-QTL populations are also under development at ICRISAT More recently, development of synthetic amphidiploids (Foncéka et al., 2009; Mallikarjuna et al., 2011) can facilitate better utilization of wild species in breeding programs as use of synthetic amphidiploids circumvent the crossing barriers between wild and cultivated species EMERGING GENOMICS AND BREEDING APPROACHES GENOME SEQUENCE DATABASE Because of large genome size and amphidiploid nature the genome and heavy costs associated, it was not possible earlier to initiate genome sequencing However due to advances in next generation sequencing and coordination of large number of partners, Peanut Genome Project (PGP)2 has been initiated recently with specific goals for sequencing the groundnut genome and developing genomic resources for use in groundnut improvement programs (see Pandey et al., 2012b) It is expected that draft genome sequence and extensive genomic and transcriptome information will be available soon that will enable deployment of modern genotyping approaches such as genotyping-by-sequencing (GBS) GBS is expected to make genotyping costs cheaper and faster and accessible to a broad groundnut community As a result, for trait mapping, genome-wide association studies (GWAS) will be in routine in coming years in groundnut breeding http://www.peanutbioscience.com/peanutgenomeproject.html www.frontiersin.org GENOMIC SELECTION Both MABC and MARS requires development of family mapping populations and identification of QTLs/marker effects before getting into the main stages of improvement programs Further due to difficulty in handling polygenic traits and sometimes in development of good mapping populations, a better approach called “genomic selection (GS)” is fast emerging as a molecular breeding approach for crop improvement Identification of superior lines with higher breeding value (genomic-estimated breeding values, GEBVs) in segregating breeding populations based on genome-wide marker profile data is the first step toward using this approach To so, a training population (TP) comprised of elite breeding lines for which multiple-season phenotyping data on agronomically important traits are available across environments is required for estimating GEBVs Parental genotypes are then selected based on GEBVs and crosses are effected to develop candidate population (CP) In other words, CP is developed from the crosses made using the lines with best GEBVs in the TP as parents (Varshney et al., 2013) GS is now preferred over MABC and MARS for improving complex traits as GS has the advantage of selecting lines based on entire genome rather than one/few small segment of genome It also enjoys the benefits of MABC and MARS by affecting selections based on genotype and prior of extensive phenotyping thus saving time and resources (Jannink et al., 2010) In order to exploit the recent advances in groundnut genomics to improve complex traits such as drought tolerance and seed yield, efforts have been initiated at ICRISAT to apply GS In this direction, a TP has been developed that includes about 300 advanced breeding lines for which historical data on their performance have already been compiled SUMMARY The conventional breeding approaches have largely utilized the available genetic variability in cultivated groundnut and to some extent the variability trapped in wild Arachis species was also used to develop improved groundnut varieties The breeding procedures used for self-pollinated crops are employed in groundnut improvement programs along with use of phenotyping tools Identifying and assessing the nature of variability for target traits, utilizing the sources of variability as parents in hybridization, and advancing the best possible genotypes after selection are the key steps in the groundnut breeding programs Pedigree, bulkpedigree, and single seed decent methods are followed to handle segregating population after hybridizing two parents Following conventional approaches, several improved groundnut varieties with high yield and tolerance/resistance to foliar fungal diseases, bacterial wilt, root-knot nematode, virus, rosette diseases, and drought were released for cultivation The released varieties have a wide range of maturity duration, ranging between 90 and over 150 days required for cultivation in various growing regions with varying LGP They belonged to different market types, viz, Spanish, Virginia, and Valencia and meet market uses (oil and food uses) and agro-climatic requirements The last decade has witnessed development of molecular marker linkage maps in groundnut that was followed by identification of markers and QTLs for target traits This paved way for deployment of molecular tools in breeding program for February 2013 | Volume | Article 23 | 11 “fpls-04-00023” — 2013/2/21 — 17:49 — page 11 — #11 Janila et al Groundnut: genetic and genomic tools efficient utilization of time and resources and improved efficiency of breeding As a consequence, the extensive breeding programs are becoming intensive with the use of molecular breeding tools Marker technologies offer approaches (GWI and AB-QTL mapping) that enable tapping of new alleles from wild Arachis species that remain under-utilized Targeting multiple traits (gene pyramiding) is another important possibility of molecular breeding approaches Groundnut breeding programs in USA, China, India, and Japan have already embarked the new technology to complement the ongoing breeding programs “NemaTAM” is the first cultivar developed through molecular breeding for resistance to root-knot nematode This was followed by “Tifguard High O/L” that has high O/L ratio and multiple resistances At ICRISAT, MABC is underway to develop cultivars with rust resistance that are now in advance generations and also pyramid resistance to rust and LLS MABC for improvement of oil quality is underway at USA, Japan, and India The uptake of molecular breeding tools REFERENCES Amin, P W., Singh, K N., Dwivedi, S L., and Rao, V R (1985) Sources of resistance to the jassids (Empoasca kerri Pruthi), thrips (Frankliniella schultzei (Trybom)) and termites (Odontotermes sp.) in groundnut (Arachis hypogaea L.) 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Janila et al Groundnut: genetic and genomic tools their inheritance pattern because of lack of effective phenotyping tools Studies on character association have resulted in identification of associated... development and deployment of genomic tools and genetic resources as well as breeding and extension activities, and its national partners in South-Asia and Sub-Saharan Africa mechanism of resistance... improvement: use of genetic and genomic tools Front Plant Sci 4:23 doi: 10.3389/fpls.2013.00023 This article was submitted to Frontiers in Plant Genetics and Genomics, a specialty of Frontiers